How to defeat Zodiark?

He is solid.When i get most of his HP down, he keeps becoming immune to magic and physical damage.
All of my characters are on lv72 / 73
I have all espers apart from Ultima (and Zodiark)
What's the best method of taking him out???

The only way to beat him at that point is to wait it out. When one paling goes down, start attacking with whatever you have. When his life is little and his physical paling goes down, finish him off with a quickening, because he will just resurrect that paling a few seconds afterwards.

The magic barrier seems to be put up alot more often if you dispel his reflect. The physical barrier he has at the top of his gambit list to just constantly refresh it from what I saw.

ie... perhaps you can find a way to pierce reflect instead of dispelling it.

If you aren't dispelling reflect and he is still raising both barriers, yea.. that is kinda difficult.
After he puts up that final physical barrier at low health, I never could get another physical attack in. He would drop his magic barrier occasionally though.

Make sure you get the Excalibur from the Great Crystal before taking him on. It's a Holy weapon, which does maximum damage to a Dark elemental like Zodiark, at least until he starts using Shift. At that point non-elemental weapons would work better. Also Black Masks absorb Darkja damage (although you'll still have to revive party members).

Make sure that you set the party's gambits for physical attacks until he starts protecting against it. Then switch those gambits to cast Scathe.

I think Opal Rings will let you cast through Reflect.

Sound lads cheers

I equipped an Opal Ring on my main attacker and set the other two to support. As long as you don't dispel reflect then he puts up the magick palling less often. Then I nailed him with Scathe again and again. Don't have everyone cast Scathe at once though. They can only cast black magick one at a time for some reason but support magick can be cast all at once. If you have only one character use scathe then you'll get in a lot more hits, especially if that character has haste and a high magick stat. I couldn't defeat him until my characters had levels in the 90s. If you're not there then go and get Ultima. Deep in the Great Crystal is a great place to level.

due to the "lag" or "wait" when casting spells, I've seen there be times that his physical barrier would fall in the middle of a scathe, holy, flare, or something else long. During this time, one of the physical attackers did get a few hits in and zodiark was waiting for my characters to finish their black spell before he cast his physical barrier again. Might have been a fluke or there might have been other factors, though.